With the proliferation of mobile communications devices has come an increased demand for new features for mobile communications devices. There is a high demand for mobile communications device features that make the devices more user-friendly, for example, by increasing the ease and accuracy with which common tasks may be performed.
Given the wide use of mobile communications devices in a variety of settings, it is important that features be simple and accurate. For example, hands-free dialing is available for many mobile telephone handsets. This obviates the need to remember telephone numbers and/or to enter commonly-dialed telephone numbers while, for example, driving a motor vehicle.
In general, a mobile communications device (e.g., a mobile telephone) has a keypad. When buttons on the keypad are pressed, the device generates an audio signal. Traditionally, this signal has been a dual-tone multi-frequency signal (hereinafter referred to as a “DTMF tone”). In addition to generating a DTMF tone for dialing purposes, a device may generate a sound to give the user feedback. For example, the device may produce a short click sound to inform the user that a button has been pressed. Often, the feedback provided to the user is the DTMF tone generated for dialing purposes.
While the DTMF tone is easily understood by the telephone networks, humans are not adept at differentiating between the multiple frequency tones generated.
Another common feature of mobile communications devices is a display. The display typically communicates data to a user. The data may include the battery status, various available features and/or menus, contacts, call status, signal strength, combinations thereof, and the like When dialing, text messaging, email, or the like, the display may list the entered characters sequentially so the user can verify that the correct characters have been entered into the device correctly.